tbuckley/cabot-search huggingface dataset:
Abstract P3060: Modeling Immune Checkpoint Inhibitor Associated Myocarditis <i>In Vitro</i>
Authors: Garrett Jensen, Xinjie Wang, Wei Zhao, Zhishi chen, Wei Yu, Nicolas L Palaskas, Clifford Stephan, Reid Powell, Joseph C Wu, Weijia Luo, Jiang Chang
Journal: Circulation Research (2023)

Introduction: Immune checkpoint inhibitor-associated myocarditis (ICI myocarditis) is a severe side effect of treating malignancies with immune checkpoint inhibitors. Patients suffering from ICI myocarditis often display an extraordinarily high mortality rate. Establishing a clinically relevant model to address the lack of identifiable risk factors, screening tests, or effective treatments is critically urgent. Hypothesis: Human ICI myocarditis can be accurately modeled in vitro. Methods and Results: We present the first cell culture-based model of ICI myocarditis. We use a novel method to co-culture human iPSC-derived cardiomyocytes (hiPSC-CM), human peripheral blood mononuclear cells, and immune checkpoint inhibitors to recapitulate critical aspects of clinical ICI myocarditis. Using this platform, we show rapid, significant cardiomyocyte necrosis after model initiation. We observe substantial disruption to hiPSC-CM cell morphology and sarcomere structure, and we use powerful multi-electrode array technology to define contractile functions and electrophysiological changes, demonstrating the critical similarities between this cell-based ICI myocarditis model and patient myocarditis. Our model also reveals an increased risk of arrhythmia, recapitulating, in vitro , the primary cause of death in patients suffering from ICI myocarditis. Finally, we demonstrate that this hiPSC-CM-based “model in a dish” can be rescued pharmacologically and identify specific leukocyte populations required for myocarditis development. In summary, we present the first in vitro model of ICI myocarditis and demonstrate its scalability, validity, patient relevance, and reproducibility. Utilizing the model can aid in accomplishing precision medicine objectives and holds significant potential for preventing and treating ICI myocarditis.
Abstract P3095: Il-1 Signaling On Vascular Smooth Muscle Cells Accelerates Atherosclerosis After Murine Kawasaki Disease Vasculitis
Authors: Shuang Chen, Youngho Lee, Malcolm Lane, Debbie Moreira, Emily Aubuchon, Kenichi Shimada, Timothy R Crother, magali Noval Rivas, Moshe Arditi
Journal: Circulation Research (2023)

Objective: We have previously shown that Lactobacillus casei cell wall extract (LCWE)-induced Kawasaki disease (KD) vasculitis significantly accelerates atherosclerosis in hypercholesterolemic mice. IL-1 signaling is known to play a key role in both KD vasculitis and in the development of atherosclerosis. Here, we investigated the contribution of IL-1 signaling on vascular smooth muscle cells (VSMCs) during KD vasculitis-induced acceleration of atherosclerosis. Methods: Tamoxifen-inducible VSMC-specific IL-1 receptor ( Il1r1) knockout ( Myh11 Cre -ERT2 Il1r1 Δ/Δ )and Il1r1 fl/fl littermate control mice, all on ApoE -/- background, were injected with either PBS or LCWE. Following induction of KD vasculitis, mice were fed a tamoxifen diet for 2 weeks to induce Il1r1 deletion on VSMCs, before being exposed to 8 weeks of Western diet (WD) to promote atherosclerosis. Results: KD vasculitis was associated with a significant acceleration of atherosclerosis, as expected. Specific deletion of Il1r1 on VSMCs reduced this effect, as characterized by significantly decreased plaque size, lipid composition, macrophage infiltration and necrotic core formation in aortic root, as well as diminished lipid accumulation in aorta en face measurements. Conclusions: Our results suggest an important pathophysiologic link between IL-1 signaling, specifically on VSMCs, and subsequent acceleration of atherosclerosis in hypercholesterolemic mice following KD vasculitis. Thus, further studies are warranted on the role of IL-1 signaling not only in acute KD, but also in the subsequent vascular remodeling and complications following acute KD vasculitis.
Abstract P3008: A Computational Model Predicts Sex-specific Responses To Calcium Channel Blockers In Mesenteric Vascular Smooth Muscle
Authors: Gonzalo Hernandez Hernandez, Samantha O’Dwyer, Collin Matsumoto, Pei-Chi Yang, Zhihui Fong, Mindy Tieu, Luis F Santana, Colleen Clancy
Journal: Circulation Research (2023)

The electrical activity of smooth muscle cells underlies the regulation of the diameter of small resistance arteries and arterioles to control blood flow and blood pressure. Historically, measurements of pressure in blood vessels and their responses to drug interventions have been based entirely on data from male animals. Recently, experiments have indicated sex-specific differences in smooth muscle. We hypothesize that the fundamental differences in ion channel expression measured in male and female cells may underlie variable responses to antihypertensive drugs between males and females. To determine if this hypothesis is plausible, we developed a computational model to investigate the effects of measured sex-specific differences in the electrophysiology and Ca 2+ signaling of vascular smooth muscle cells. Contrary to established models suggesting that K V 1.5 channels are the most prominent K V channels regulating membrane potential, our model predicts that K V 2.1 channels play an unexpectedly primary role in the control of membrane potential in female but not in male cells. In addition, we found that sex-specific differences in the amplitude and voltage dependencies of L-type Ca V 1.2 currents between males and females cause higher Ca 2+ influx and higher [Ca 2+ ] i , in female than in male mesenteric smooth muscle cells. To simulate sex differences in the regulation of resistance arteries and arterioles, we developed an idealized vessel model by connecting smooth muscle cells through simulated resistances to represent gap junctional coupling. The model predictions suggest that female arterial smooth muscle is more sensitive to clinically used Ca 2+ channel blockers than male smooth muscle. Our computational framework initiates the first steps toward the investigation of the potential sex-specific impact of antihypertensive drugs, which may lead to more effective treatment for hypertension.
Abstract P3085: The Macrophage Landscape Across The Lifespan Of A Human Cardiac Allograft
Authors: Xiao Li, Diwakar Turaga, Chang-Ru Tsai, Rich Gang Li, Joseph Spinner, Edward Hickey, Iki Adachi, James F Martin
Journal: Circulation Research (2023)

Much of our knowledge of organ rejection after transplantation is derived from rodent studies. We used single-nucleus RNA sequencing (snRNA-seq) to investigate the inflammatory milieu in pediatric cardiac allografts at different stages post transplantation. We distinguished donor from recipient-derived cardiac cells using naturally occurring genetic variants embedded in snRNA-seq data. Donor-derived cardiac resident macrophages dMPs, which accompany the cardiac allograft into the recipient, are rapidly lost post transplantation. On the other hand, monocyte-derived macrophages from the recipient (rMPs) quickly populate the heart post transplantation and form two macrophage populations, rMP1 and rMP2. While rMP2s have cell signatures similar to dMPs, they lack pro-reparative phagocytic activity and instead express profibrotic genes. In contrast, rMP1 express genes consistent with hallmarks of cellular rejection. Our data further support the conclusion that rMP1s activate a subset of natural killer (NK) cells, turning them into a cytotoxic cell population. Self-amplifying reciprocal signaling occurs between rMP1s and NKs, which is consistent with a key mechanism for clinical rejection. Our data reveal an imbalance of donor-derived and recipient-derived macrophages in the pediatric cardiac allograft after heart transplantation. Moreover, we observed a clear functional dichotomy of recipient-derived macrophages. At different stages after heart transplantation, rMPs contribute to acute adverse damage to the myocardium and chronic organ failure.
Abstract P3071: Targeting Neutrophil Sting And Type I Interferon Activation In Myocardial Ischemia-Reperfusion Injury
Authors: Maegan L Brockman, Lanfang Wang, John W Calvert, Rebecca D Levit
Journal: Circulation Research (2023)

Introduction: Inflammation following myocardial ischemia/reperfusion (MI/R) plays a significant role in damaging cardiomyocytes and influencing infarct size, with neutrophils being the most rapid and numerous cells in the post-MI/R heart at 24 hours post reperfusion. Preliminary single-cell RNA sequencing data shows type I interferon (IFN) responding neutrophils are present in the hearts of mice 24 hours post-MI/R. The following study aims to address how the type I IFN responding neutrophil phenotype identified in single-cell RNA sequencing data affects cardiac inflammation in MI/R. We hypothesize that STING and type I IFN activation in neutrophils in the early stages of inflammation can exacerbate inflammation, causing further damage to the heart in MI/R. Methods: Male C57BL/6J mice (10-11 weeks old) underwent 60 minutes of ischemia followed by reperfusion, and were dosed with either vehicle, a STING inhibitor (H151), or an IFNAR1 antibody (ab) at reperfusion and at 24 hours following reperfusion. Cardiac function was assessed two weeks post-reperfusion via echocardiography and tissue samples were collected for histological analysis. Results: Mice treated with IFNAR1 ab showed significant improvement in ejection fraction (44.9% ± 6.8) compared to mice treated with vehicle (31.9% ± 6.2; One-way ANOVA, N=5-6, p&lt;0.05). Additionally, mice treated with IFNAR1 ab showed significant improvements in left ventricular end systolic volume (LVESD) (3.16mm ± 0.52) compared to vehicle treated mice (3.89mm ± 0.40; One-way ANOVA, N=5-6, p&lt;0.05). Mice treated with H151 showed significant improvement in ejection fraction (43.8% ± 7.1) compared to mice treated with vehicle (31.9% ± 6.2; One-way ANOVA, N=5-6, p&lt;0.05). Treatment with H151 or IFNAR1 ab reduced scar size (7.22% ± 3.6; 7.88% ± 3.1%) compared to mice treated with vehicle (9.74% ± 3.7; N=5-6). Conclusion: These data show that targeting the early IFN response in MI/R can improve cardiac function, and provide a basis for studies identifying the effects of the neutrophil specific STING and type I IFN activation following MI/R. If correct, this pathway could be a powerful and clinically feasible point of intervention to improve cardiac recovery after MI/R.
Abstract P3193: Cardiac Glutamine Metabolism As NAD+ Generating Pathway During Chronic Hypoxia
Authors: Ivan Menendez-Montes, Ashley Solmonson, Ana Helena MAcedo-Pereira, Alisson C Cardoso, Yuji Nakada, Suwannee Thet, Ralph DeBerardinis, Hesham A Sadek
Journal: Circulation Research (2023)

Cardiovascular disease morality relies in the inability of the adult mammalian heart to regenerate damaged tissue due to the inability of the adult cardiomyocytes to proliferate. This lack of proliferation in the adult heart is due to an increased DNA damage and activation of the DNA Damage response upon an increase of mitochondrial ROS generation. We have previously shown that modulation of mitochondrial metabolism towards glucose oxidation at expenses of fatty acid utilization can induce adult cardiomyocyte proliferation and support cardiac regeneration. Moreover, by modulating the oxygen levels and, thus, cardiomyocyte metabolism, by chronic hypoxia exposure, we were also able to induce cardiomyocyte proliferation and cardiac regeneration in adult mice. Remarkably, our metabolomic studies of the hypoxic hearts did not show increase of lactate production, a hallmark of hypoxic metabolism in order to regenerate NAD+ required for glycolysis and ATP production under low oxygen conditions. Interestingly, glutamine metabolism is one of the most compensatory pathways in these conditions. Glutamine can be metabolized to its conversion into glutamate, which can enter in the Krebs’ Cycle, but also feed the malate-aspartate shuttle. This shuttle has the ability to generate cytoplasmic NAD+. Here, we hypothesize that, during chronic hypoxia exposure, the heart uses glutamine as a fuel to regenerate cytoplasmic NAD+ as an alternative to lactate production. By means of carbon labeling and metabolic flux studies in vivo, we have proven that glutamine contribution to the malate-aspartate shuttle is enhanced during hypoxia in the heart. Moreover, we have determined that glutamine supplementation during hypoxia in cell culture increases cytoplasmid NAD+ levels, confirming the contribution of glutamine catabolism to NAD/NADH balance during hypoxia. Overall, we show that glutamine metabolism is an important adaptation to hypoxic metabolism in the heart and describe a new mechanism of metabolic rewiring under hypoxia beyond the classic lactate production upon glycolysis upregulation.
Abstract P3198: Spermidine Ameliorates Aortic Valve Degenerations By Improving Mitochondrial Biogenesis
Authors: Sahmin Lee, Naaleum Song, Eunhye Ji, Jeong Eun Yu, Kyoung-Hee Choi, Kyung-Gon Kim
Journal: Circulation Research (2023)

Aortic stenosis is the most common heart valve disease in the elderly, and aging is a leading factor. However, there is no medical treatment yet except for an operation. We investigated that mitochondrial function deteriorated in isolated human aortic valve interstitial cells (hAVICs) from the patients who had aortic stenosis (Figure A, B). We examined the therapeutic effect of spermidine (SPD) which is known to enhance mitochondrial function in the treatment of diseased hAVICs. As a result, we showed the expression of fibrosis, inflammation, and calcification markers decreased after the SPD treatment. Using the LDLR knockout mice model fed a high-fat diet, we found that the mitochondrial function in mouse AVICs improved after the SPD treatment, and the thickening, inflammation, and calcification of aortic valve leaflets significantly decreased in the SPD-fed mice (Figure C, D). Ingenuity pathway analysis from proteomic data in this animal model suggested the IRS2-AKT-TP53-SIRT1-DNMT1 pathway as a treatment mechanism and we could confirm that TP53, SIRT1, and PPARG increased while IRS2, AKT and DNMT1 were inhibited by the treatment of SPD in ex-vivo and in vitro experiments. In addition, we found that 5-azacytidine, as a DNMT1 inhibitor, induces the mitochondrial biogenesis-related genes by lowering mtDNA hypermethylation in hAVICs. In conclusion, spermidine ameliorates the mitochondrial function through the IRS-AKT-TP53-SIRT1-DNMT1 pathway in AVICs and the inhibition of DNMT1 and mtDNA hypermethylation improves mitochondrial biogenesis which can be a treatment mechanism for aortic stenosis.
Abstract P3045: MicroRNA-31-5p Is Upregulated During Neointima Formation And Promotes Smooth Muscle Cell Proliferation And Migration By Regulating Krüppel-like Factor 4 (KLF4)
Authors: Simon Gürlach, Katrin Kalies, Fiene Daniel, Jan Michael Köster, Solveig Boettcher, Laura Hehl, Kai Knoepp, Jochen Dutzmann, Jan-Marcus Daniel, Daniel Sedding
Journal: Circulation Research (2023)

In the context of CVDs, microRNAs (miRs) have emerged as potential therapeutic targets for preventing adverse vascular remodeling and restenosis, given their ability to modulate multiple signaling pathways and cellular processes. Here, we propose that targeting miR-31-5p might be an effective approach to enhance vascular healing and regeneration in a cell-specific manner, thereby limiting angioplasty-related complications. A screening of murine neointimal tissue for differentially regulated miRs revealed robustly increased expression levels of miR-31-5p over time. Subsequently, expression levels of miR-31-5p were confirmed by qRT-PCR in human coronary artery endothelial cells (EC) and -smooth muscle cells (SMC). Further, the effect of miR-31-5p on cellular function was investigated and possible targets were identified and confirmed on mRNA and protein level. Expression analysis revealed a significant upregulation of miR-31-5p (p&lt;0.0001) in C57BL/6J mice following wire-induced injury of the femoral artery at 7 and 21 days. In vitro, miR-31-5p was significantly upregulated in SMC (p&lt;0,05 ) following serum stimulation, whereas only a slightly enhanced expression was observed in EC. On a functional level, miR-31-5p revealed dissenting effects on EC and SMC: Migration and proliferation were not altered in EC (p&gt;0.05). In contrast, knockdown of miR-31-5p significantly reduced the migration (p&lt;0,05) and proliferation in SMC (p&lt;0,01) without detectable apoptotic effects. Systematic in silico target screens suggested KLF4 as potential target. Knock down of miR-31-5p resulted in a significant upregulation of KLF4 in SMC (p&lt;0,01), whereas overexpression resulted in a significant downregulation of KLF4 in SMC (p&lt;0,05) on mRNA- and protein level. Here, we report that miR-31-5p is robustly upregulated during neointima formation and seems to exert a functional role in SMC rather than EC since knockdown of miR-31-5p was able to prevent SMC proliferation and migration. Mechanistically, KLF4 identified as a direct target of miR-31-5p can mediate the observed effects. Thus, miR-31-5p might represent an attractive target to selectively modulate SMC dysfunction following vascular intervention, limiting neointima formation in treated vessels.
Abstract P3069: ScRNA-seq And Flow Cytometry Based Analysis Reveals That Chronic Heart Failure Associates With Enhanced Activation And Clonal Expansion Of T Cells With Predictive Autoreactive Capacity
Authors: Wesley T Abplanalp, Maximilian Merten, Sebastian Cremer, Tina Rasper, Kathrin Holz, Bianca Schuhmacher, Igor Macinkovic, Lukas Tombor, David John, Andreas M Zeiher, Stefanie Dimmeler
Journal: Circulation Research (2023)

Background: Heart failure (HF) is marked by adverse remodelling and chronic inflammation causing impaired function of the heart and poor prognosis. While much is known about the immune response immediately after MI, little is known of the role of the immune system in chronic HF. Our aim is to elucidate the response of T cells to HF. Methods and Results: In a pilot study assessing healthy controls (HC) and HF patients (n=16), scRNA-seq showed an enhanced T cell activation profile in HF patients. A confirmation cohort of n=180 HC and HF patients using flow cytometry of immune cells confirmed an increase of T cell memory/effector cells (HF=65%, HC=53% activated T cells). Correspondingly, circulating antigen presenting cells showed augmented inflammatory profiles (ICAM-1, TREM-1). Given that T cells showed strong activation profiles in HF patients, we investigated whether T cells are preferentially clonally expanded in the same patients. Bulk T cell receptor (TCR) sequencing revealed that TCR diversity was significantly reduced (p=0.03) along with clonal expansion of T cells in HF patients. To assess what T cells might be targeting, we utilized epitope prediction tools to identify 22 unique human-derived epitopes found only in HF patients. ScRNA-seq of CD45+ sorted cardiac-derived and circulating cells of the same HF patient (N=1) versus healthy controls (n=4) showed clonal expansion of TCRs in the cardiac tissue and blood in HF and epitope prediction confirmed epitopes found in bulk TCR sequencing. When modelling this in mice, a scRNA-seq post-MI time course also found an accumulation of specifically pro-inflammatory (Th17) T cells in the heart at days 14, 28 and 48 post-MI. To assess the impact of immune dysregulation in HF on cardiac cells, we cultured the secretome of HF or HC immune cells with endothelial cells and found decreased viability of endothelial cells and increased monocyte adhesion to stimulated endothelial cells (p=0.005). Conclusion: This study suggests that chronic HF may drive persistent T cell activation and clonal expansion, with potential cardiac-relevant autoimmune implications causing or promoting adverse remodelling. These data also provide additional insights for therapeutic cardio-immunological interventions.
Abstract P3192: Prdm16 Regulates Cardiac Metabolic Genes Through Perm1
Authors: Omid Rouzbehani, Michael Goodman, Bo Sun, Rajeshwary Ghosh, Amira Sabri, Junco S Warren, Andrew P Landstrom, Sihem Boudina
Journal: Circulation Research (2023)

The heart is a metabolically demanding organ that requires significant amounts of energy to function properly, and even minor metabolic deficiencies during development can lead to heart failure. Cardiomyopathies are a group of conditions that affect the heart's contractile function, and PRDM16 deficiency is a primary cause of cardiomyopathies associated with 1p36 deletion syndrome in humans. Conditional deletion of Prmd16 in the heart causes a spectrum of cardiac phenotypes including left ventricular non-compaction, late-onset heart failure, and dilated cardiomyopathy. Still, the mechanisms underlying these cardiac phenotypes with loss of Prdm16 are not fully understood. We and others demonstrated that lack of Prdm16 in the heart causes alterations in fatty acid (FA) oxidation and oxidative phosphorylation (OXPHOS) gene expression. Further, we now show that Prdm16 cardiac deletion reduces the expression of key regulators of FA oxidation and OXPHOS genes including Perm1. Loss and gain of Prdm16 function in vitro confirmed a cell-autonomous regulation of Perm1 by Prdm16 in H9c2 rat cardiomyoblasts and neonatal rat ventricular myocytes (NRVMs). Prdm16 ChIP-sequencing analysis of embryonic hearts revealed direct binding of Prdm16 to the promoter of Perm1. Prdm16 binding to Perm1 promoter was further confirmed by ChIP-qPCR in H9c2 cells. Knockdown of Prdm16 in NRVMs reduced maximal mitochondrial respiration, which was rescued by over-expressing Perm1. Further, PERM1 mRNA was diminished in human induced pluripotent stem cells-derived cardiomyocytes (iPSC-CMs) derived from a patient with a PRDM16 mutation (Q187X). These results are evidence that PRDM16 is an upstream regulator of PERM1 in the heart.